جستجوی مقالات مرتبط با کلیدواژه « انتشار گازهای گلخانه ای » در نشریات گروه « آب و خاک »

The agricultural sector as the main infrastructure for food security is one of the most important economic sectors of societies and its average share in the GDP of 161 countries studied in 2019 is about 11 percent. In parallel with the role of this sector in the provision of food security and employment of countries with negative side effects on basic resources and the environment, which led governments to reconsider their policies related to the agricultural sector. Governments can, willingly or unwillingly, affect the environmental sustainability of the agricultural sector in a variety of ways. This article focusing on non-systematic review approach and using the reports of authentic international institution (including FAO, OECD, WTO, etc.), deals with the implications of the agricultural sector and policy developments of the recent decade in the OECD member countries. The findings show that agricultural support policies tend to have a negative impact on the environment. Market price supports policies and payments based on output, and payments based on unconstrained variable input use found to be the most environmentally harmful. In contrast, fully decoupled support payments based on non-current crop area are the least harmful. Soil nutrient balance; Greenhouse gas emissions; Water abstraction for agricultural activities; and biodiversity of agricultural lands (crop diversity and homogeneity of landscapes) are among the key indicators that its improvement and deterioration helps to explain the relationship between agriculture and the environment and recent studies by OECD countries show significant gains in some of these indicators.

The purpose of this study was to investigate the environmental impacts of sugarcane production in Hakim Farabi Agro-Industry Company through life cycle assessment method in the 2019 crop year. The production of one ton of sugarcane considered as the functional unit. The required data was collected through face-to-face interviews with managers and experts. The results indicated that diesel fuel, electricity, urea fertilizer and direct field emissions from sugarcane cuttings had the greatest effect on all sectors in the studied effect groups. The evaluation showed that Marine aquatic Ecotoxicity released 103447.86 kg 1, 4-DB per one ton of sugarcane which has the highest potential for environmental damage. Therefore, three scenarios were defined to evaluate the effects of sugarcane cultivation on the impact categories in order to reduce water consumption, reduce fertilizers and chemical pesticides consumption and reduce electricity and diesel fuel consumption. The emission rate of this impact category after applying the first, second and third scenarios is estimated to be 99714.6, 95628.02 and 91894.77 kg 1, 4-DB per one ton of sugarcane, respectively. N2O, CO2 and CH4 greenhouse gas emissions were estimated to be 0.915, 261 and 0.506 kg, respectively. After applying the scenarios, CO2, CH4 and N2O emissions were estimated as follows: N2O emissions were 0.871, 0.827 and 0.784 kg, respectively, CO2 emissions were 251, 240 and 230 kg, respectively and CH4 emissions were 0.491, 0.475 and 0.460 kg, respectively.

One of the main sources of greenhouse gas (GHG) emissions is the use of energy for groundwater pumping. Reducing energy consumption is very important to achieve the environmental sustainability and decrease the climate change impacts. In this paper, the amount of greenhouse gas emissions from groundwater pumping in the Guilan’s aquifers was investigated. Firstly, groundwater depletion and the types of pumps for water pumping were examined in the current condition; then, the values of consumed energy, GHG emissions and climate change indicator of the current condition were estimated. The primary investigations showed that 55 percent of wells in the studied region had a diesel engine pump, while 51.3 percent of the required energy for groundwater pumping was supplied by electric pump. Calculated total GHG emissions and the value of climate change indicator in the current condition were equal to 8.98 and 7.59 Milion kg CO2 eq , respectively. In order to achieve environmental sustainability and energy security, scenarios of replacing electric pumps and applying solar energy were examined. The results of the scenarios showed that diesel fuel wells had no significant effect on the reduction of greenhouse gas emissions, but the use of solar energy reduced them. GHG emissions, in comparison with the base scenarios, were decreased by 44.4% in June, July and August, respectively, by applying the scenario of using the solar pump in agricultural section. Therefore, it is preferred to apply policies in future planning to use renewable energies such as solar energy instead of diesel and electricity energy.